You'd expect two players in a competitive tennis match to grind out every point, battling to the end.
Not American tennis player Jack Sock, playing against Australian Lleyton Hewitt during a Hopman Cup match on Tuesday night.
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Hewitt served, with the umpire calling out on the ball. Sock decided to intervene, saying, "It was in, if you want to challenge it," to a rather bemused Hewitt.
"Challenge it!" Sock shouted, before Hewitt decided to tell the umpire to check the replay. What a sportsman — and Sock was right too, by the way.
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